Embed
Email

Description

Document Sample

Shared by: ajizai
Categories
Tags
Stats
views:
6
posted:
12/3/2011
language:
English
pages:
15
SECTION C. PROJECT DESCRIPTION



PROJECT TEAM TABLE

Table 1. Research Participants and Role in Project

Name Title/Affiliation Expertise Role in Project Time*

Concrete and Composite PI, Research coordination, Development,

Dawn Asst. Prof. of CEE, 2(1.25) Months

Structures, PBEE, Component Tests (lead), Design

Lehman UW All Years

Experimental Research recommendations, Outreach

Co-PI, Development, Component Testing, 2 Months

Jeffrey Asst. Prof. of CEE, Steel Structures,

Analytical modeling (lead), Design and PBEE All Years

Berman UW Experimental Research

recommendations (0.5M Y2)

Cement-Based

Katherine Asst. Prof. of CEE, Co-PI, Sustainable concrete material 2(0.67) Months

Materials and

Kuder SU development and characterization (lead) Y1&2, 1 M Y3

Composites

Prof. of CSEE, Steel and Concrete Co-PI, UB Experiments (lead), Composite wall

Andrew 2(0.67) Months

Deputy Director Structures, PBEE, development, Design and PBEE

Whittaker All Years

nees@Buffalo Experimental Research recommendations

Rob Technical Service Cement-Replacement Senior Personnel, Sustainable concrete material 1 Month

Shogren Engineer, Lafarge Concretes development and characterization Y1 & Y3

Principal, Walter P. Sustainable Engineering Senior Personnel, Collaboration to develop

Dirk 1 Month

Moore, Chair SEI Chairperson of SEI specimen design and detailing, Development of

Kestner Y1 & Y3

Sustainability Com. Sustainability Comm. LEED-like rating, Technology transfer (lead)

Director of Seismic Design of Steel Senior Personnel, Collaboration to develop

Rafael 1 Month

Design, Walter P. Structures, Seismic specimen design and detailing, Development of

Sabelli Y1 & Y3

Moore, AISC TC-9 Design Codes LEED-like rating, Technology transfer

GSRs Grad. Student Development of design concepts and experimental designs, process, 50% time

UW/UB Researchers archive, and evaluate data to assess wall performance, analytical models Y1-3

Seattle University seniors who will contribute to the development of 2 students 50%

Undergrad. Student

UGRs sustainable concrete, perform material testing and characterization, and Y1, 100%

Researchers

participate in summer research activities at UB and UW. summer Y1-3

Rick Educational Developing educational Development of educational tools for green Varies, 1 – 3

Hartman Consultant learning tools engineering for K-6 students and their teachers months

A practice committee of prominent practicing engineers will be assembled to advise the project team on specimen design, design

recommendations and assist with dissemination and technology transfer through committees, conferences, and the sample design.

*In time column, the time extended and budgeted are both indicated with and without parentheses, respectively.



EXPERIMENTAL FACILITIES TABLE (ASSUMED PROJECT START DATE OF 10/1/2009)

Table 2. Experimental Facility Usage

Preparation Preparation Testing Start Testing

Facility Experiment Description

Start Date Duration Date Duration

Static Testing - Specimen 1 (include experimental setup) 10/1/2010 (Y1) 8 Months 6/1/2011 2 Months

nees@Buffalo









Static Testing - Specimen 2 4/1/2011 (Y1.6) 3 Months 7/1/2011 1 Month



Static Testing - Specimen 3) 4/1/2011 (Y1.7) 4 Months 8/1/2011 1 Month



Static Testing - Specimen 4 (include setup modification) 6/1/2011 (Y1.7) 4 Months 10/1/2011 2 Months

All nees@Buffalo specimens to use: (1) Two 450-kip, 40-inch stroke actuators; (2) 185 gpm servovalves; (3) two

220-kip, large-stroke actuators; (4) high-flow hydraulic distribution manifold; (5) reaction wall and strong floor in

new NEES laboratory; (7) advanced instrumentation and DAQ system; (8) digital video; and (9) telepresence

UW Long-term compression testing, anchorage walls 2/1/2010 (Y0.3) 3 Month 5/1/2010 5 Months



FUNCTIONAL BUDGET

Table 3 shows the functional budget and Figure 1 illustrates the distribution of funding to the various

project activities. As shown, the vast majority of the project funding is dedicated to the experimental

activities at nees@Buffalo.



1

Table 3. Functional Budget

Category Y1 Y2 Y3 Amount %

Research $385,918 $378,989 $275,239 $1,040,146 86.9

nees@UB $222,794 $225,713 $156,003 $604,510 50.5

UW $81,312 $100,836 $0 $182,148 15.2

SU $66,524 $31,380 $1,000 $98,904 8.3

Disposal $0 $0 $6,340 $6,340 0.5

Other $15,288 $21,059 $111,896 $148,244 12.4

Data $0 $3,864 $36,875 $40,738 3.4

EOT $5,215 $5,364 $62,587 $73,166 6.1

Mangmnt $8,395 $11,644 $22,964 $43,004 3.6

Total $399,529 $399,861 $397,665 $1,197,055 100.0



SUMMARY OF PROPOSAL PREPARATION DISCUSSION WITH

NEES@BUFFALO EQUIPMENT SITE Figure 1 Allocation of Funds

This proposal was a collaborative effort developed by the

investigators over the course of the past four months. Professor Whittaker, Deputy Director of the

nees@Buffalo Equipment Site, discussed the scope and detail of the UB testing program with UB Site

Operations Manager Tom Albrechcinski, Technical Services Manager Mark Pitman and IT Manager

Goran Josipovic in early 2009. Mr. Albrechcinski provided costs for materials, specimen fabrication and

specimen disposal that were used to prepare the budget for the UB test specimens.



VISION

Meeting tomorrow’s challenge of reducing the environmental impact of engineered structures means

needing to do more than taking existing structural framing systems and forcing them into LEED or other

related environmental certification requirements. It means reimagining structural systems to be inclusive

of the current and future engineering challenges with an eye towards the environment. Although reducing

environmental impact is just part of the sustainability solution, it is important in and of itself. The

project’s vision is to promote environmental stewardship in structural engineering in three ways: (1) by

minimizing material use, eliminating unnecessary materials, and using recycled materials, (2) minimizing

the carbon footprint, and (3) optimizing constructability.



Performance-based earthquake engineering (PBEE) also serves to promote environmental stewardship.

Today it is common for a developer of a “green” building to make significant initial investments in high

performance mechanical building envelope systems to reduce the environmental impacts associated with

energy use of the building’s life. It is also common for mechanical engineers to perform energy analyses,

which exceed the minimum code requirements. Code-based structural design, which uses prescriptive

details and likely excessive materials, will not protect this expensive investment from the full-range of

seismic demands; a more performance-based approach is needed. A structural system developed to

minimize the environmental impact and simultaneously minimize seismic damage to itself and its

contents is truly green in the eyes of the earthquake engineer.



An innovative composite wall system, shown in Figure 2, is proposed to meet these combined objectives.

The wall comprises a recycled steel shell with end caps. The concrete fill is a self-consolidating concrete

(SCC) containing (90-100%) supplemental cementitious materials (SCM). Staggered, embedded steel

studs are attached to the steel shell to engage composite action and restrain local buckling (see cutout in

Figure 2). With respect to the seismic and environmental performance objectives, the proposed system:

 Maximizes the use of recycled materials including steel and SCM concrete.

 Minimizes the carbon footprint with SCM concrete.

 Optimizes the constructability by using stiffened steel skin plates that act as stay-in-place

formwork and reinforcement for the wall, and SCC to reduce labor associated with concrete

placement.



2

 Possesses exceptional seismic performance by limiting foundation damage and local buckling.

Use of SCM concrete presents an engineering challenge, as the cure time to full strength is far longer than

that of convention concrete. A composite system, with its permanent formwork, provides an elegant

engineering solution by sustaining construction and other loads via the studded steel skin plates.



A research project with coordinated material and structural experimental,

analytical and integrated practical technology development and transfer tasks is

proposed. Each has theoretical significance, coordination with other research tasks,

and contribution to practice. The material study will be conducted by researchers

from Seattle University (SU), a primarily undergraduate institution, and is aimed at

evaluating and modeling the SCM concrete. The SCM material, developed by the

SU research team, will be utilized in the wall and tested to assess the immediate

and time-dependent response at the University of Washington; the anchorage detail

will also be explored experimentally. These results will culminate in the large-

scale testing of the walls to generate experimental and performance data to develop

much-needed engineering models for composite wall design and their connections.

These results will be combined with and extended by numerical studies. Finally,

the team will partner will leaders in sustainability in structural engineering from

Walter P. Moore to lay the foundation for PBEE tools and to develop sample Figure 2

building designs to compare the environmental impact and seismic performance of Innovative

the proposed and conventional systems. Future advances in the system design may Composite Wall

include its use in precast construction, which will further improve construction efficiency and reduce

carbon footprints, and expand the green seismic construction into heavy civil and nuclear infrastructure.



LITERATURE REVIEW

The research impetus for developing engineering methods for sustainable composite walls are twofold: 1)

to improve the performance of conventional reinforced concrete walls, one of the most commonly used

seismic resisting system in current construction, and 2) to develop a system that meets the objectives of

sustainability. However, a primary obstacle in achieving this system is the lack of research on the seismic

behavior of composite walls and cement-replacement concretes. The literature review presented below

addresses: the shortfalls of the seismic response of reinforced concrete walls, the possible improvements

offered by composite walls and the data lacking to support these hypotheses, and the limited data on the

engineering and time-dependent properties of SCM concretes.



Reinforced Concrete Walls

Reinforced concrete walls are stiff and strong and are a commonly used seismic resisting system.

Although earthquake damage has been observed in walled buildings, as indicated in 3(a), generally they

have been deemed to perform well and they are commonly used the primary lateral load resisting system

(Wallace and Moehle 1993). As such there has been a keen interest in the structural engineering

community to improve understanding of the earthquake response of walls and numerous research studies

have been undertaken. A more recent example of a wall test is a specimen tested by Adebar and his

associates intended to simulate a seven-story wall (Adebar et al. 2007) in which a single actuator was

used to simulate the full lateral load and the demands in the lower levels are not modeled. The damage

sustained by the wall is shown in Figure 3(b) and do not clearly correspond to the post-earthquake

observations. In contrast, there are the results of the NEES research program studying the seismic

performance of walls (Figure 3c). Use of the LBCB equipment at the NEES MUST-SIM facility has

permitted more accurate simulation of the loading demands from the upper stories and the advanced

controller has permitted multiple actuators to be used to simulate floor-shearing (inertial) loads. As a

result, as shown in 3c, the laboratory damage pattern more closely agrees with that observed in the field

for midrise buildings. The figure shows the damage concentrates at the base of the wall, limiting the drift

capacity to between 1% and 1.5%, which falls well short of the codified drift limit.

3

Figure 3 Wall Damage Observed Field and Laboratory



Beyond these seismic response limitations, reinforced concrete walls have numerous issues regarding

constructability and environmental impact. In seismic design, the reinforcing detailing requirements are

extensive and the construction of the cage is tedious

(Figure 4) and time-consuming; a result of the anchorage

and confinement requirements. A tour of recent high-rise

construction in Seattle and Bellevue, WA shows that the

majority of these buildings have been constructed with

reinforced concrete core walls as the lateral load resisting

system. As Mehta (2009) notes, the carbon footprint of

the concrete industry is large and the emission of CO2 is

largely attributed to the production of Portland cement.

Replacing a commonly used yet mediocre and

complicated framing system with a seismically improved Figure 4 Composite and RC Walls

and environmentally friendlier system is a logical place to (Corus 2009, Stevenson and Panian 2009)

start to meet the structural engineering challenges facing today’s professional engineer.



Steel-Concrete Composite Walls

Relative to reinforced concrete walls, composite walls greatly simplify the construction process.

Composite walls have begun to be used in construction outside of the United States. For example, Corus,

the UK steel producer, has developed a product called CoreFast to use steel panels connected by a series

of welded steel bars filled with concrete. Originally developed as a blast-resistant system, the system has

been used in multi-unit residential construction (Gough and Grubb 2007) and design recommendations

are available from the manufacturer with behavior limited to elastic response. According to the company

literature, the primary benefits of the system are the expedited construction time and reduced material use.



The enhanced constructability may have an even larger impact on the constructability of the structural

walls in seismic regions, which is evident when comparing the panels with the cage construction shown in

Figure 4. However, composite walls have not been used in seismic construction, in part because there has

been limited research on the seismic performance of composite shear walls. AISC 341-05 (AISC 2005)

contains limited seismic design requirements for composite shear walls. The steel plate(s) are designed to

carry the design shear, neglecting any contribution of the concrete, and specific compressive and flexural

composite design expressions are not provided.



Without experimental data development of even simple design expressions is not possible. Prior research

has included steel-concrete-steel sandwich double skin panels (Zhao and Han 2006) and double-skin

composite elements (Wright et al. 1991). Although these investigations did result in some design

recommendations, the experiments were not focused on cyclic behavior. Other research has focused on

the details and response of the composite panels, which are related to but not directly applicable to the

composite walls addressed here. For example, Hossain and Wright (2004) investigated profiled



4

connection details for double skin composite shear walls to improve the buckling strength and reduce

stiffener requirements, resulting in basic design equations for elastic shear strength response. Liang et al.

(2004) analytically investigated double skin composite plates to study the local buckling of steel plates

under combined biaxial compression and shear. The composite infill wall systems subjected to seismic

loading studied by Zhao and Asteneh (2004) does indicate promise of ability to sustain large drift ratios,

but the system differed from composite walls in that boundary-frame elements were present. A current

research project on composite walls, conducted by Professor Kreger (work undergoing) at Purdue

University and sponsored by the Pankow Foundation, represents a first-step towards understanding the

behavior of the seismic response of these systems and an important collaborator if this project is funded.



The literature suggests that composite walls hold promise for seismic engineering but need additional to

ensure that they are capable of sustaining multiple, inelastic drift cycles. Robust connection details

between the concrete and steel are needed. Equally important is the connection between the composite

wall and the adjacent components, in particular the foundation elements. This

deficiency is common and noted in many areas of composite component research

(Roeder et al. 2002). Although different approaches have been researched (e.g.,

Hajjar 2002, Fujikura et al. 2008, Morino et al. 2003 and Azizinamini and Schneider

2004), most use complicated details with large connection components and excessive

welding requirements. Researchers at the University of Washington have developed

a simple yet effective connection for CFT columns using an annular ring welded to

the base of the tube as shown in Figure 5 and an anchorage depth of one column

diameter (Kingsley et al. 2005). The experimental results show the specimen is

capable of reaching drift ratios of 4 to 6% without damage and sustaining drifts Figure 5 CFT

exceeding 8%. Of course, the technology is not directly applicable to walls, as Anchorage

circular CFT have a different distribution of normal stresses around the

circumference of the steel tube, symmetric and large confining pressures, and a larger footing-to-cross-

sectional area ratio for columns than walls. However, the concepts and technologies of the research

findings are relevant and their application and adaption is discussed in the research program.



Cement-Replacement Concrete

Portland cement is a hydraulic cement that, when combined with water, undergoes a chemical reaction in

which calcium silicate hydrate (cementitious gel) and calcium hydroxide (lime) are produced. Calcium

silicate hydrate is the glue that holds all the constituent materials together and contributes to the strength

and durability of the composite. Lime is a deleterious component that can cause expansive behavior.

Supplementary cementitious materials (SCMs) are a form of mineral admixtures that are often used in an

effort to develop sustainable concrete mixes (Malhotra 2006). SCMs are generally waste materials, such

as fly ash, silica fume and slag that have cement-like qualities and are typically used to partially replace

cement. Use of SCMs is becoming increasingly popular to produce sustainable concrete because it

reduces the amount of cement needed, thereby reducing the CO2 emissions that occur during cement

production, and utilizes waste that would otherwise be land-filled and reduces cost. SCMs possess

hydraulic and/or pozzolanic reactivity. SCMs with hydraulic reactivity can react with water without the

presence of a hydraulic component, similar to the self-cementing behavior of Portland cement. In the

presence of water, a pozzolan will react with the calcium hydroxide released from the hydration reaction

to form additional calcium silicate hydrate, thus improving strength and durability. Pozzolanic reactions

occur more slowly than hydraulic reactions, causing a delayed time of set and slower strength

development.



Minimizing the amount of Portland cement in concrete is a key aspect of minimizing the carbon footprint

in construction (Stevenson and Panian 2009). For example, a recently constructed reinforced concrete

building in northern California attempted to achieve this objective by using concretes with both 50% and

70% cement-replacement. However, the authors report challenges with using concretes with large



5

cement-replacement values including strength gain and finishing. Where overcoming these obstacles in

reinforced concrete construction is difficult at best, composite construction naturally lends itself to the use

of even higher cement-replacement concretes, as the rate of strength gain and finishing are not critical

engineering or construction parameters. Therefore, the composite wall is a solution for improving

sustainability in seismic engineering practice.



Research Program Justification

A primary future focus of the building industry nowadays is improving environmental stewardship, which

is generally quantified with LEED credits. Although structural engineering has largely been sidelined

from this enterprise, forward-looking structural engineering firms, research laboratories, and the SEI

committee on sustainability are looking at strategies to use optimal amounts of recycled materials and

materials with minimal environmental impact for new construction, building systems that can be reused

and recycled and new building construction with reduced long-term landfill mass and carbon footprint.



Materials that are deemed “green” are most easily LEED credited. The most commonly LEED-termed

green material are SCM concretes, however SCM concretes are difficult to use in structural engineering

applications with key challenges stemming from the rate of curing and finishing (Stevenson and Panian

2009). As a result, SCM concretes are not used extensively and building framing systems are not playing

a role in environmental stewardship. The framing system proposed herein is different. The shortcomings

of SCM concretes are overcome here by placing it within a permanent steel skin system with key benefits

including a) SCM concrete strengthening over an extended timeframe without the need for formwork, and

b) faster floor-to-floor cycle times because the steel skins can resist construction gravity loads.

Importantly, the SCM will delay local buckling of the steel skins through the anchorage of the skins to the

concrete with studs.



Theorizing about a practical system and developing it into a viable framing system are quite different and

a significant amount of work is needed to realize the latter. Analysis and theory alone are not sufficient. A

robust experimental program and associated numerical simulations are needed to substantiate these new

systems and materials and to characterize a framing system suitable for inclusion in a building codes and

standards such as the International Building Code (ICC 2006) and ASCE-7 (ASCE 2005), respectively.



Research Plan

A compelling research program is proposed here and is illustrated in Figure 6. The research program uses

appropriate laboratory facilities, existing equipment, and experimental and technical expertise for each of

the three testing programs proposed. As such, the facilities, personnel, and equipment were selected with

thought and purpose. The figure lays out the research tasks. The timeline is provided at the left of the

figure. For each task, the tasks objective, lead personnel, principal outcome, and interaction with other

task are indicated. The illustration within each task provides a visual clue as to its aim. UW and SU

student involvement with the nees@Buffalo tests is illustrated with airplanes, as travel is required. At the

bottom of the figure the primary technical and the EOT outcomes are listed. The following paragraph

provides an overview of the research plan. Specifics about each task, its schedule, objective, staffing,

research methods to be used, and anticipated outcomes are described in the individual task subsections.



The research project utilizes an integrated team of researchers with expertise in material, concrete, steel,

and composite testing in partnership with industry leaders in sustainable structural engineering to develop,

test, extend, validate, and disseminate an innovative, recycled composite wall system for seismic

engineering. The developmental phase of the project will be a team effort to brainstorm, refine and

finalize transformative yet practical design and detailing concepts for the wall system (Task 1). In

parallel, the material testing will be conducted at Seattle University and LaFarge Cement using their

combined cemetitious testing equipment to demonstrate that the high-strength 100% SCM concrete is

practical and to support the development of the time-dependent design and constitutive models (Task 2).

In support of the detailing concepts and material tests, component tests will be conducted at the



6

University of Washington using the 2.4-million pound Universal Testing Machine to evaluate the

construction and other long-term response of parts of the composite walls (Task 3). The wall system tests,

conducted at nees@Buffalo, will utilize the large capacities of the actuators, reaction floor and walls as

well as experimental equipment developed for PI Whittaker’s Squat Wall NEES research project (Task

4). These capabilities, together with the expertise that PI Whittaker brings to the proposal makes

nees@Buffalo the NEES site to select for large-scale testing of this innovative wall system. Task 5 will

use numerical simulation models to both predict the experimental response (to aid in the set up) and

validate the measurements to extend the study to lay the groundwork for PBEE and other design methods.

Finally, the results will be distilled into a sample design to compare the seismic, construction and

environmental efficiencies of the proposed framing system and its conventional counterpart (Task 6).



Task 2 Task 1 (All): Task 3 (Lehman):

(Kuder/Shogren): Develop Design, Anchorage and Time-

SCM Concrete Mix and Detailing Dependent Loading

Concepts

Outcomes:

Year 1 Innovative and

10/09- Practical Designs

and Details

9/10

Outcomes:

Outcomes: High Cement Recommended

Replacement Concrete Anchorage Details, Time-

Mixes, Properties, and Task 4 (Whittaker): Dependent Compressive

Models

Full-Scale Experiments Response

at NEES@Buffalo

SU

UW Graduate

Undergraduate Student to UB

Year 2 Students to UB

10/10-

9/11

Task 5 (Berman): Task 6

Analytical (Kestner/Sabelli):

Models/Design & Sample Building

PBEE Tools Designs





Outcomes: Rich Unique

Data Sets on Composite

Wall Behavior

Year 3

10/11-

9/12

Outcomes: Outcomes: Sample

Modeling & Design Designs, Performance

Recommendations, Trial and CO 2 Comparisons

Fragility Curves with RC Walls





PRODUCTS • Rich, First of Their Kind Data Sets on Composite Walls

• Innovative, “Green” Seismic Force Resisting System

• Initial Performance Based Earthquake Eng. Recommendations

• Sample Building Designs for Dissemination to Practice

• EOT FOCUS: K-12: Engineered Recycled Materials Ed. Modules

• EOT FOCUS: Transfer via SEI/ACI Committees

• Dissemination at Conferences and Graduate Course Content



Figure 6: Project Tasks, Integration, and Products





7

Task 1 (All): Development of Practical Design and Detailing Concepts for Wall and SCM Concrete

The proposed system uses new materials, designs, details, and construction methods to achieve the dual

objectives of mitigating seismic damage and environmental impact. Of course, throughout the

development of the proposal, the project team has brainstormed and solidified ideas on each aspect of the

project, and those results are presented throughout the proposal. Task 1 will serve to further the

development of the proposed concepts and solicit input from all involved on the: (i) modified mix designs

for the high-strength SCM concrete, (ii) wall cross sections details with a particular focus on the end cap,

(iii) stiffening, confining, and bond details for the steel skin plates, (iv) anchorage connections, and (v)

practical construction and fabrication methods.



To successfully achieve this idea-generating task, the entire team must be engaged. Professor Lehman

will facilitate the task, with Mr. Sabelli and Mr. Kestner of Walter P. Moore taking the lead on the design

concepts and Dr. Shogren taking the lead on the SCM concrete design. These men are leaders in their

respective fields and will guide the research team to ensure that the details of the proposed system are

developed to meet the present and future needs of the practicing engineers who will implement this

system. By informing the research team on the state-of-practice with regard to the environmental impacts

of current structural systems, strategies implemented to minimize those impacts, and alternative strategies

that are not presently implemented and note the barriers preventing implementation, the practicing

engineers will help shape the details and design methods of the proposed system. Input from other

practicing engineers that will serve on the practice committee will also be solicited. This will ensure that

the system properly addresses environmental objectives while maintaining constructability.



This task, and this project, represents an ambitious goal to achieve in a short time. Here the time

constraint will be managed using Web-Ex based meetings, which was successful for the team during the

proposal development. The task will be initiated as the project commences, and carried out over the first

four months. The task products include the design (including concrete and structure) and detailing

concepts for testing, evaluation, validation, and dissemination throughout the remaining tasks.



Task 2 (Kuder (lead)/Shogren): Characterizations of High-Replacement SCM Concrete

This work will focus on the use of slag and Class-C fly ash to produce an environmentally sustainable,

self consolidating concrete (SCC) mix design in which most, if not all, of the Portland cement is replaced.

Typically, slag demonstrates more hydraulic reactivity than Class C fly ash, resulting in earlier strength

gains (Gesoligu and Ozbay 2007). However, Class C fly ash has more pozzolanic properties, which could

contribute to superior strength and durability long-term (Naik et al. 2005 and Yazici 2008). In addition to

single SCM replacement mixes, binary and ternary mixes will be evaluated in an attempt to optimize the

performance of the SCMs. Table 4 provides some of the first-of-its-kind data on high-replacement SCM

concrete, in this case with a target strength of 3,000 psi. As indicated in the table, the impact of the SCM

on the early strength is quite substantial and cannot be ignored in the design or in construction, as echoed

by (Stevenson and Panian 2009). Here, the objective is to further this by developing mix designs to

achieve a target strength of 6000 psi, which in line with modern concrete material requirements. The

partnering of PI Kuder and Dr. Shogren is the best way to achieve the task. This partnership is enhanced

by the generosity of Lafarge North America, who has assured donation of all concrete to the project.



Table 4. 3000-psi Target CR Concrete Mix Designs (Lafarge and Central Pre-mix Concrete Data)

% Cement % Slag 7-day (psi) 14-day (psi) 28-day (psi)

10 90 2710 4500 5950

5 95 2280 3670 4740

0 100 1650 2900 3950







8

Five test categories are proposed; the specific references and duration are provided in Table 5. Task 2.1

evaluates the material properties of the SCMs, including chemical composition and particle size

distribution. A variety of slag and Class C fly ashes will be tested, since SCMs can vary greatly based on

the plants and operating conditions from which they originate. The workability (Slump flow, L-box, V-

funnel) of the SCC mixes will be evaluated to study placement and setting behavior. Compressive

strength and elastic modulus of the concrete mixes will be measured at 7, 14 and 28 days and then at 28-

day increments up to one year to establish the time-dependent mechanical properties, which is of central

importance to Tasks 3 and 4 and the project as a whole. At the same time as Tasks 2.2 and 2.3 are

underway, free and restrained shrinkage tests will be performed to evaluate the durability of the mixes.

Once promising mixes have been identified, Task 2.5 will be conducted in which the effect of the mix

designs on formwork pressure will be evaluated. The rheology of the mixes will be modified as needed to

increase the thixotropy, which reduces formwork pressure (Assad et al. 2003 and Assad 2004).



Table 5. SCM Concrete Test Matrix

Test Category Experimental Methods/References Duration

SCM characterization ASTM C618 & ASTM C989 2 months

Fresh state properties European Glne for SCC & ASTM C403 12 months

Mechanical properties ASTM C39 & ASTM C469 12 months

Durability ASTM C157, ASSHTO T160 & M PP34 12 months

Rheology – formwork pressure 4 months



The task results and data will be used to develop time-dependant engineering expressions for the

mechanical properties, as warranted, and to modify commonly used concrete constitutive relations to

account for the time-dependencies so important in SCM concretes.



Task 3 (Lehman (lead)/Berman) Anchorage, Time-Dependent Tests on Walls with Recycled Materials

Development of a new system requires substantial understanding of the connections and as-built response

during and just after construction. In this system, two practical issues must be addressed in conjunction

with the system response testing (Task 4):

 Task 3.1: Anchorage details for the connection of the walls to the foundation. As noted in the

literature review, without validated connection details, use of any seismic component in actual

construction cannot be realized. Here, development of a simple yet robust connection able to sustain

the seismic demand and maximize energy dissipation is the goal.

 Task 3.2: Behavior under immediate and longer loads. Use of SCM concrete is a challenge, in part

because of the extended cure time. Although not a specific issue for seismic response, the immediate

and short-term mechanical properties of the concrete and composite wall must be known to ensure

stability during and after construction. This task focuses on these variables.



These experiments are basic and do not require use of, and would not

represent optimized use of, a NEES facility. Instead the structural

engineering laboratory at UW is used to permit the experiments to be

conducted in parallel. As shown in the functional budget, the Task 3

experiments represent 15% of the total budget and 17% of the

experimental costs.



Task 3.1: Wall-to-Foundation Anchorage Connection

The primary design objective for the anchorage connection is that it be

able to develop the moment strength of the composite wall, and

therefore the tensile capacity of the steel. Simple, yet innovative

anchorage details will be considered for the critical interface between Figure 7 Anchorage Pull-Out

the concrete foundation and the double skin shear wall. The details will Experimental Setup

draw on PI Lehman’s extensive experience in developing anchorage

9

connections for composite structural members and use available structural members, such as staggered

angles, to ensure adequate embedment and pullout resistance without creating a plane of weakness.

Flange connections have been found to work well in CFT (Figure 3) and can also reduce required

anchorage lengths relative to stud connections in foundations that are congested with reinforcing steel. To

avoid creating a plane of weakness, the depth of the flanges within the concrete foundation will be varied

along the wall’s length.



Figure 7 shows an anchorage test. Each specimen consists of a partial-width of a composite wall

embedded into foundation. The test matrix will evaluate the influence of: (1) studs, (2) debonding, and (3)

anchorage depth, on response. The results will be used to generate connection design recommendations

and to complete the design of the specimens for the large-scale experiments at nees@Buffalo (Task 4).



Task 3.2: Time-Dependent Compressive

Response

The time-dependent compressive behavior

of the composite wall system must be

understood prior to field implementation.

To investigate this, the 2.4-million pound

universal testing machine (UTM) in the

SEL at UW will be used (Figure 8). A half-

scale (or larger) wall specimen will be

constructed under the UTM and filled with

the selected SCM concrete mix. Although

long-term properties of the selected mix

will be determined in Task 1, it is Figure 8 Time-Dependent Compression Test

important to study the behavior of the

composite system as a whole, and to study the changes in formwork pressure with time. Strain gages on

the steel skin plates will be used to monitor formwork pressure and compressive stress in the skin plates

throughout the pouring curing and loading stages. The specimen will be loaded with increasing

compression loads representing the addition of construction loads. To simulate application of gravity

loads to the wall in a building, the compression force will not be directly applied to the wall specimen;

instead the wall will be loading in through shear-tab connections that are welded to the exterior of the

plate, as shown in Figure 8. Axial deformation, skin plate strains, and changes in formwork pressure will

be carefully monitored by a combination of strain gauges and a non-contact optical displacement

measurement system. This testing is critical if this system is to be used in practice as one of the reasons

practitioners are reluctant to use high-replacement SCM concrete is the slow gain of compressive

strength.



Task 4 (Whittaker (lead)/Lehman/Berman): Large-Scale Wall Tests at nees@Buffalo

The scope of the experimental program was prepared after the research team reviewed the literature and

to realize the project vision. The scope of this project will build on that of co-PI Lehman and Professor

Lowes who have focused on conventional reinforced concrete flexure-critical (tall) walls in their NEESR

project (Brown et al. 2006, and Lehman et al. 2008) and that of co-PI Whittaker who is addressing the

behavior of conventional reinforced concrete squat (shear-critical) walls. Specifically, Task 4 will provide

robust thesis-oriented data for each Ph.D. student involving both physical and numerical simulation and

enable meaningful participation of undergraduate students (from Seattle University). The specific

objectives for this task are:

1. Generate large-scale test data to examine and describe the response of rectangular, recycled-material

composite walls to cyclic lateral loading.

2. Provide a substantial body of performance data (numerical and visual) to:

a. Validate the detailed design models to be used in the numerical simulation tasks of the project.



10

b. Enable development of teaching tools to involve undergraduate students in research and

development of curriculum modules in the curriculum development portion of this project.

c. Enable the PIs and other researchers, via the NEES Data Repository, to develop efficient demand

parameters, fragility curves and loss-related acceptance criteria for double skin composite walls.

3. Engage the students from UW and SU in all aspects of the testing. Form student teams at UW, SU

and UB, led by the Ph.D. students at UW. Assign students meaningful tasks that go beyond lab-tech

work on strain gauging: make them responsible for video data and Krytpon or Lieca 3D laser data

acquisition systems, the synchronization of these measurements with the conventional measurements,

the interpretation of this data and the presentation of their findings at appropriate forums.

4. Engage Mr. Sabelli, Mr. Kestner, and other advisory engineers from practice in specimen design

decisions. Introduce practicing engineers to NEES and involve them in tele-participation activities

through the project web site and WebEx teleconferences.

5. Exercise key aspects and equipment of the nees@Buffalo Site with demanding testing activities.

6. Disseminate the results using the project web site, the resources of NEES Inc, and the appropriate

ACI and AISC materials committees



This phase of the project will be conducted at the nees@Buffalo Equipment site under the supervision of

co-PI Whittaker. Four large-scale specimens will be tested with preliminary dimensions of 8-in. thick and

10-20 feet high (depending on specimen), 0.25-in. steel skin thickness and specified concrete strength of

6000 psi. Study parameters include (1) aspect ratio, (2) stud spacing and geometry (Figure 3) and (3) axial

load ratio. Specific values and details have been preliminarily developed by the project team and include

comparison with both tall and squat reinforced concrete walls. Stud spacings will be varied to evaluate

conservative design expressions based only on plate buckling equations, to evaluate expressions based

solely on concrete damage prevention, to evaluate economically-driven spacings. The stud lengths and

head dimensions will be determined in consideration of gaining full anchorage while minimizing local

concrete damage. These discussions will take place during and the test matrix will result from Task 1.



Figure 9 shows the proposed test set-up at the nees@Buffalo Equipment Sites using NEES actuators (see

Table 2). The loading system proposed for the squat wall NEESR tests at UB will be used to test the

composite walls. A separate system will be used to impose

axial load. The multi-dof controllers available at the

nees@Buffalo site can control multiple horizontal actuators to

simultaneously impose lateral loads. Lateral restraint will be

provided at one end of each specimen so that coupled with the

horizontal actuators, the specimens will displace in plane.



Measurements and photographs will be taken to mark the

progression of damage during the test. After each test the

specimens will be taken out of the test setup for further

documentation of observed damage. Failure surfaces will be

carefully documented, and materials sampled to establish as-

built properties. The specimens will be disposed of following

the relevant environmental protection practices and protocols

established at nees@Buffalo. The cost of specimen disposal is Figure 9 nees@Buffalo Composite Wall

included in the budget. To the best of our knowledge, the specimens tested in this task will be the only

walls of this type tested in the world to date. Equally important, they will be the largest composite wall

specimens tested to date. The resulting data, which will be archived and curated by the Ph.D. students at

UB and UW will enable the development and validation of robust numerical tools as described in Task 5.

These validated numerical tools will substantially expand the scope of the testing program described

above to consider alternate aspect ratios, steel skin thicknesses, and concrete strengths, in a most cost-

effective manner.



11

Task 5 (Berman (lead)/Lehman/Whittaker): Analytical Models for Wall Behavior and Engineering

The number of wall parameters studied in the experimental program is limited due to the high cost and

necessity of large-scale testing. The objectives of this task are to:

 Recommend methods of modeling composite wall systems for structural design.

 Develop basic design recommendations by exploring parameters beyond the scope of the

experimental study.

 Develop damage states and preliminary fragility curves for use in performance based design and

implementation in the ATC-58 framework.



The first phase will consist of modeling the nees@Buffalo experiments. Several different software

packages will be used, including packages common in research settings (Abaqus, VecTor, and OpenSees)

and those common in design (CSI Perform). The concrete constitutive models developed in Task 2 will be

used. For VecTor and OpenSees analyses, the steel plates will be treated as external smeared

reinforcement. For Abaqus analyses, a more detailed treatment of the exterior skin plates will be

permitted, allowing plate local buckling to be investigated. The rich experimental data will be used to

develop and validate the models.



The validated models will be used to conduct limited parametric studies to evaluate the impact of

important design parameters such as wall aspect ratio, the equivalent reinforcing steel of the steel plate

skins, wall thickness, material properties and axial load ratio. The results of the analyses will be the

generation of fragility curves for damage states observed in the testing.



Calibration of analytical models for use in design (e.g., CSI Perform models) will be developed and

validated using the procedure described above in partnership with Mr. Kestner and Mr. Sabelli from

Walter P Moore (WPM), as well as others on the post-award selected advisory committee. The results of

these Perform analyses combined with the test results will form the basis of design and modeling

expressions and methods for composite wall systems.



Task 6 (Kestner, Sabelli from WPM): Sample Building Designs and Performance Comparison

To validate the system and disseminate the results to a wide body of practicing engineers, the engineers

from Walter P. Moore will develop sample building designs for the composite wall system using recycled

materials and conventional reinforced concrete walls. These sample building designs will demonstrate the

practicality, seismic performance, and reduced environmental impact of this innovative composite shear

wall system, and these enhancements will be more clearly illustrated when compared with a conventional

wall system. Once complete, the information will be disseminated through committees including the SEI

Committee on Sustainability, AISC committees, and presentations and publications.



Walter P. Moore (WPM) will use Building Information Modeling to compare the resulting structural

material quantities with a conventional concrete wall system. Environmental impact will be estimated

based on two current sustainability rating systems and the overall reduction in environmental impacts,

likely quantified as CO2 emissions. Additionally, the reduction in embodied impacts in terms of tangible

units such as transportation and energy consumption will also be quantified. WPM has extensive

experience in quantifying the environmental impact of projects and Mr. Kestner is an expert in this area.



Seismic performance will be assessed using nonlinear response-history analysis in CSI Perform using the

modeling techniques developed in Task 5 for composite walls. Based on the damage states and fragility

curves developed in Task 5, estimates of wall repair costs subject to design ground motions will be made

and compared with results for traditional reinforced concrete walls. Some consideration for performance

of nonstructural components, as estimated by peak drifts, will be made.









12

Expected Outcomes

The primary outcome of this project is a system that minimizes its environmental impact while achieving

exceptional seismic performance. As part of achieving this comprehensive objective, there are important

research findings and products that will be developed along the research trajectory. These are the specific

outcomes of each research tasks, illustrated in figure 6, and highlighted below.

 Task 1 will result in designs and details for the composite wall system that are practical, efficient, and

likely to have robust seismic response.

 Task 2 on developing and characterizing the 100% (or nearly) cement-replacement concrete will

result in expressions for the time-dependant engineering properties of these materials and will be used

to modify current concrete constitutive models.

 Task 3, aimed in part at developing and validating constructible anchorage details for composite

walls, will result in experimentally-verified design expressions for connecting composite walls to

foundation elements. This is a critical yet missing component of the seismic design procedure for

these systems and this outcome should move the composite structural wall system forward in its

application to seismic design.

 The primary outcome of Task 4 will be test results on and data from large-scale composite walls that

use recycled materials, maximize constructability and enhance seismic performance.

 Task 5 will use the results of Tasks 3 and 4 to validate an analytical model of the tested walls and

extend these results using the validated model. This effort will result in validated design and analysis

methods for practice, preliminary fragility curves will lay the foundation to establish PBEE tools for

this system, and an initial recommendation for practical nonlinear analysis models.

 Task 6 will produce a set of sample composite wall designs and compare their seismic performance

and environmental impact with conventional walls for dissemination.



Education, Outreach, and Technology Transfer Activities

The educational, outreach and technology-transfer (EOT) activities affiliated with this proposal include

conventional activities including education of graduate and undergraduate students (Tasks 2, 3, 4 and 5),

outreach and technology transfer to the practicing and academic engineering communities. For the

students at Seattle University, a primary educational objective, voiced by Professor Kuder, is broadening

their exposure to the research process, which is achieved through their integral participation in the

research activities at UW and nees@Buffalo (Tasks 3 and 4). One of the limitations of multi-institutional

research teams is difficulty in integrating and uniformly understanding research progress, challenges, and

findings throughout the program; this educational transfer activity will be achieved through weekly or bi-

weekly WebEx conference calls facilitated by the faculty but with the discussion organized, led, and

carried out by the student(s).



Outreach and technology-transfer to the academic and practicing engineering communities will be

achieved through presentations and publication of the research results at engineering firms, technical

conferences, and conferences of interested engineering societies (Tasks 5 and 6). Task 6 specifically

addresses the transfer of the engineering, analysis, and design technology through the development of

sample building designs, including an environmental impact assessment. To ensure these activities come

to fruition, funding for travel and consulting for Mr. Kestner and Sabelli is specifically in place. This

sample building designs will go beyond a traditional seismic example comparison. A Building

Information Model will be develop and used to assess the environmental impact of the proposed system

to a conventional reinforced concrete wall, and will include quantification of CO2 emissions,

transportation, energy consumption, as well as material and construction related metrics.



As noted by the National Academy of Engineering, engaging young people in engineering is critical to

increasing the number and quality of future engineers. To that end, a specific and unique EOT activity,

specifically, the development of a K-12 educational learning module on engineering with recycled

materials is proposed. This effort is lead by Rick Hartman, a leader in the development of educational

13

toys for enrichment and learning (see Mr. Hartman’s bio for additional information), who will work in

collaboration with PIs Lehman and Berman and their graduate students on this activity. Specifically, Mr.

Hartman will develop, field test and disseminate a series of engaging hands-on projects for K-8 students

that emphasize the science, excitement, and challenges of designing structures for earthquakes while

remaining “green”. Using a variety and mixture of recycled, “green”, and conventional building materials,

Mr. Hartman will produce a prototype workshop and companion video that teach students how to

construct their own fun and surprising toys that demonstrate important concepts about engineering

structures for earthquakes while challenging them to consider its impact on the environment. Mr. Hartman

will offer live presentations of his workshop to schools and museums. His tools will be made available so

that teachers and parents may conduct their own workshops based on the projects developed.



Data Archiving and Sharing Plan

This project will adhere to the requirements of the NEESinc Data Sharing and Archiving Policies and

Guidelines and to newer requirements established by the NEES operations awardee. Raw data from the

shared use experiments will be uploaded within 24 hours of the test where possible. All appropriate

documentation will be provided within the framework of the NEES repository. Interpreted data will be

uploaded in a reasonable time, after interpretations are made and discussed with the project team to

ensure accuracy of results. Full data release to the public will be performed in adherence with the NEES

requirements and any new requirements of the NEES operations awardee. As noted in the functional

budget, there are significant funds dedicated to the archiving and curating of the data. Those funds will

support time for students and researchers to organize, document, and upload the data. Findings will also

be disseminated at conferences, including the NEES Annual Meetings, and through journal publications.



Payload Opportunities

Sample opportunities for payload projects are listed below.

 Development of advanced sensor concepts for damage detection in composite wall systems.

 Development of novel anchorage connection details.

 Further development and validation of hybrid testing algorithms for stiff structural systems.



Project Implementation Plan



Project Management Plan and Organizational Chart

A multi-institutional research project such as this one needs careful consideration of the management of

the research activities, researcher interaction, and technology and information transfer. As shown in

Figure 10, the project has participants from the west (SU and UW), the south (WPM), and the east (UB).

With an ambitious project such as this, it is not possible with the time allotted to solely depend on travel

to accomplish these objectives. Instead, we must turn to technology. The project will be managed by PI

Lehman and she will facilitate the realization of these important activities. Most importantly, we will use

conference calls and when

appropriate Web-Ex, in particular

for the design development and

research exchange that must

happen. As indicated in Figure 6,

each PI is the lead on a specific

task, and they will assume the

managerial and other

administrative responsibilities for

that tasks, including (if

appropriate) support and advising Figure 10. Organizational Chart

of graduate and undergraduate

students, design of all aspects of test or analysis program, including ensuring accurate data reduction and



14

analysis, and posting data to NEES Central. Travel is allotted to enable transfer of research technology

within the project team and to the practicing engineering community. Funds for SU and UW students to

participate in the nees@Buffalo testing are included and these students will be under the supervision of PI

Whittaker during their stay, as indicated in the chart.



Project Web Site

The project team will develop a website that will be hosted on UW web servers and will prove an

important resource for project team members and interested parties alike. The website will provide

information regarding current project activities, results, schedules. For the project team, the website will

serve to facilitate access to NEES central; for outsiders NEES Central links will be provided data viewing

and live experimental observation. The EOT products will be posted as they become available.



Project Risk Mitigation Plan and Schedule are included in the supplementary documents.



Results from Prior NSF Support

Project Title: NEESR-SG: Seismic Behavior, Simulation and Design of Complex Wall Systems

NSF Award Number: CMS-0421577 Amount/Period of Support: $1,537,000 10/2004 – 9/2008-2009

Principal Investigator: L. Lowes, with co-PIs D. Lehman (UW), D. Kuchma (UIUC), J. Zhang (UCLA)

Summary of the Results: The research seeks to improve understanding of the seismic performance of

reinforced concrete walls with complex configurations. Results include stiffness- and damage-

prediction models for use by practicing engineers and an analytical and experimental investigation of

code-compliant coupled-walls.

Development of Human Resources: At Universities of Washington and Illinois, two students have

completed MS degrees and five are currently working towards MS degrees. At the Universities of

Illinois and California, two students are working towards PhDs. Also several undergraduate students

are gaining research experience.

Publications: Papers have been published and presented at conferences. Two papers are in preparation.



Project Title: NEESR-SG: Smart and Resilient Steel Plate Shear Walls for Reducing Earthquake Impacts

NSF Award Number: CMMI- 0830294 Amount/Period of Support: $1,531,077.00 10/2008 – 9/2012

Principal Investigator: J. Berman w/L. Lowes (UW), M. Bruneau (SUNY Buffalo), T. Okazaki (UMinn)

Summary of the Results: The research seeks to develop a new lateral-load resisting system combining

self-centering moment frame technology with steel plate shear technology and is also investigating

key issues that are barriers to steel plate shear wall implementation. Results to date include

characterization of column demands in steel plate shear walls and development of analytical models

for the resilient shear wall system.

Development of Human Resources: At UW and SUNY-Buffalo, a total of 2 PhD students and 2 MS

students are supported. Three undergraduate students from Seattle University have been participating.

Publications: One journal paper from the project is under review.



Project Title: NEESR-II: Sidesway Collapse of Deteriorating Structural Systems

NSF Award Number: CMS-0421551 Amount/Period of Support: $449,320; 10/2004 – 9/2008

Principal Investigator: PI H. Krawinkler (Stanford University), co-PI A. Whittaker (UB)

Summary of the Results: The completed research project involved integrated numerical and

experimental studies of steel moment frame structures from elastic behavior to collapse. Two models

of four-story structures were tested on a NEES earthquake simulator at UB in 2007. A comprehensive

database of experimental information has been assembled and used to propose hysteretic models for

steel moment frame construction. Numerical models have been implemented in OpenSees to trace the

response of the tested frames through collapse.

Development of Human Resources: One student at Stanford University (Dr. D. Lignos) completed his

PhD degree in 2008. Undergraduate students at UB worked on the research project in 2007 and 2008.

Publications: Conference papers have been presented. One journal paper has been submitted.

15



Related docs
Other docs by ajizai
Fall 2010
Views: 0  |  Downloads: 0
Math 111
Views: 0  |  Downloads: 0
Training_listing_275360_7
Views: 1  |  Downloads: 0
C4-051739
Views: 0  |  Downloads: 0
DEFINITIONS
Views: 0  |  Downloads: 0
Unit POPULATIONS
Views: 0  |  Downloads: 0
albhed
Views: 0  |  Downloads: 0
price_list
Views: 9  |  Downloads: 0
By registering with docstoc.com you agree to our
privacy policy

You are almost ready to download!

You are almost ready to download!